Instead of using one single light source, COB LEDs can be spaced for better uniformity in order to avoid hotspots or low intensity areas in the grow room. A practical example would be that instead of having one big 600W HID fixture that would create a hotspot, we could have 6 COB LEDs producing the same amount of light, while consuming less and providing a way better spread.
COB chips can produce a large amount of lumens with less energy which will give you bigger yield with less energy costs. Comes in very large sizes for commercial grow ops, Very low power consumption. These lights have a full spectrum output that is more similar to natural sunlight than the red, blue and purple LEDs that you usually see in grow rooms.